diff --git a/common/src/main/java/org/implab/gradle/common/sources/BuildVariant.java b/common/src/main/java/org/implab/gradle/common/sources/BuildVariant.java
new file mode 100644
--- /dev/null
+++ b/common/src/main/java/org/implab/gradle/common/sources/BuildVariant.java
@@ -0,0 +1,32 @@
+package org.implab.gradle.common.sources;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.gradle.api.Action;
+import org.gradle.api.Named;
+import org.gradle.api.NamedDomainObjectProvider;
+
+import org.gradle.api.artifacts.ConfigurationPublications;
+
+public abstract class BuildVariant implements Named {
+
+    private final Map<String, VariantSourceSet> variantSourceSets = new HashMap<>();
+
+    private final SourceSetsSpec sourceSetsSpec = new SourceSetsSpec();
+
+    public void sourceSets(Action<? super SourceSetsSpec> action) {
+        action.execute(sourceSetsSpec);
+    }
+
+    public void outgoing(Action<? super ConfigurationPublications> action) {
+
+    }
+
+    public class SourceSetsSpec {
+        void add(NamedDomainObjectProvider<GenericSourceSet> sourceSet) {
+            var variantSourceSet = new VariantSourceSet(sourceSet);
+            variantSourceSets.put(sourceSet.getName(), variantSourceSet);
+        }
+    }
+}
diff --git a/common/src/main/java/org/implab/gradle/common/sources/SourcesPlugin.java b/common/src/main/java/org/implab/gradle/common/sources/SourcesPlugin.java
--- a/common/src/main/java/org/implab/gradle/common/sources/SourcesPlugin.java
+++ b/common/src/main/java/org/implab/gradle/common/sources/SourcesPlugin.java
@@ -1,16 +1,11 @@
 package org.implab.gradle.common.sources;
 
-import org.gradle.api.Action;
+import org.gradle.api.GradleException;
+import org.gradle.api.NamedDomainObjectContainer;
 import org.gradle.api.Plugin;
 import org.gradle.api.Project;
 import org.gradle.api.logging.Logger;
 import org.gradle.api.logging.Logging;
-import org.gradle.api.tasks.Copy;
-import org.gradle.api.tasks.Delete;
-import org.gradle.api.tasks.TaskContainer;
-import org.gradle.api.tasks.TaskProvider;
-import org.gradle.language.base.plugins.LifecycleBasePlugin;
-import org.implab.gradle.common.core.lang.Strings;
 
 /**
  * This plugin creates a {@code sources} extension which is
@@ -18,42 +13,24 @@ import org.implab.gradle.common.core.lan
  *
  */
 public abstract class SourcesPlugin implements Plugin<Project> {
-    private final Logger logger = Logging.getLogger(SourcesPlugin.class);
+    private static final Logger logger = Logging.getLogger(SourcesPlugin.class);
 
-    private final String POLICY_NAME = "SourcesPolicy";
-
-    private final String EXTENSION_NAME = "sources";
+    private static final String SOURCES_EXTENSION_NAME = "sources";
 
     @Override
     public void apply(Project target) {
-        target.getPlugins().apply(LifecycleBasePlugin.class);
-
         var sources = target.getObjects().domainObjectContainer(GenericSourceSet.class);
-        var tasks = target.getTasks();
-        var clean = tasks.named(LifecycleBasePlugin.CLEAN_TASK_NAME);
-
-        target.getExtensions().add(EXTENSION_NAME, sources);
-
-        sources.configureEach(configureSourceSet(tasks, clean));
+        target.getExtensions().add(SOURCES_EXTENSION_NAME, sources);
     }
 
-    private Action<GenericSourceSet> configureSourceSet(TaskContainer tasks, TaskProvider<?> clean) {
-        return sourceSet -> {
-            var name = sourceSet.getName();
-
-            logger.info("{}: Processing source set '{}'", POLICY_NAME, name);
-
-            var taskName = "clean" + Strings.capitalize(sourceSet.getName());
+    public static NamedDomainObjectContainer<GenericSourceSet> getSourcesExtension(Project target) {
+        var extensions = target.getExtensions();
 
-            logger.info("{}: Register task '{}' of type [{}]", POLICY_NAME, taskName, Copy.class.getTypeName());
+        @SuppressWarnings("unchecked")
+        var extension = (NamedDomainObjectContainer<GenericSourceSet>)extensions.getByName(SOURCES_EXTENSION_NAME);
 
-            var task = tasks.register(taskName, Delete.class, self -> {
-                self.delete(sourceSet.getOutputsDir());
-            });
-
-            clean.configure(self -> {
-                self.dependsOn(task);
-            });
-        };
+        if (extension == null)
+            throw new GradleException("Sources extension isn't found");
+        return extension;
     }
 }
diff --git a/common/src/main/java/org/implab/gradle/common/sources/VariantSourceSet.java b/common/src/main/java/org/implab/gradle/common/sources/VariantSourceSet.java
new file mode 100644
--- /dev/null
+++ b/common/src/main/java/org/implab/gradle/common/sources/VariantSourceSet.java
@@ -0,0 +1,19 @@
+package org.implab.gradle.common.sources;
+
+import org.gradle.api.NamedDomainObjectProvider;
+
+public class VariantSourceSet {
+    private final NamedDomainObjectProvider<GenericSourceSet> sourceSet;
+
+    String getName() {
+        return sourceSet.getName();
+    }
+
+    public VariantSourceSet(NamedDomainObjectProvider<GenericSourceSet> sourceSet) {
+        this.sourceSet = sourceSet;
+    }
+
+    public NamedDomainObjectProvider<GenericSourceSet> getSourceSet() {
+        return sourceSet;
+    }
+}
diff --git a/common/src/main/java/org/implab/gradle/common/sources/VariantsPlugin.java b/common/src/main/java/org/implab/gradle/common/sources/VariantsPlugin.java
new file mode 100644
--- /dev/null
+++ b/common/src/main/java/org/implab/gradle/common/sources/VariantsPlugin.java
@@ -0,0 +1,29 @@
+package org.implab.gradle.common.sources;
+
+import org.gradle.api.GradleException;
+import org.gradle.api.NamedDomainObjectContainer;
+import org.gradle.api.Plugin;
+import org.gradle.api.Project;
+
+public abstract class VariantsPlugin implements Plugin<Project> {
+    public static final String VARIANTS_EXTENSION_NAME = "variants";
+    public static final String OUTGOING_VARIANTS_EXTENSION_NAME = "outgoingVariants";
+
+    @Override
+    public void apply(Project target) {
+        var variants = target.getObjects().domainObjectContainer(BuildVariant.class);
+        target.getExtensions().add(VARIANTS_EXTENSION_NAME, variants);
+    }
+
+    public static NamedDomainObjectContainer<BuildVariant> getVariantsExtension(Project target) {
+        var extensions = target.getExtensions();
+
+        @SuppressWarnings("unchecked")
+        var extension = (NamedDomainObjectContainer<BuildVariant>)extensions.getByName(VARIANTS_EXTENSION_NAME);
+
+        if (extension == null)
+            throw new GradleException("Variants extension isn't found");
+        return extension;
+    }
+
+}